This invention relates to alarm mechanisms for locks and particularly to alarm capability for pin tumbler locks.
Intrusion detection systems are used on openings into buildings to notify guards of attempts by unauthorized persons to gain entry. Typically sensors are mounted on the inside of a door and do not sound an alarm until entry is actually accomplished.
Locks used to secure doors can be alarmed by placing a switch on the operating mechanism or the lock bolt. However, that approach has the same result as placing sensors on the inside of a door; an alarm will not be sounded until the lock is turned and opened.
The invention disclosed herein provides alarm capability for the locking system. An alarm will be sounded as soon as the attack begins, even if the key is used by unauthorized personnel, or by otherwise authorized personnel at an unauthorized time.